Seen in Print

[webenda]

The definition of insanity is doing the same thing over and over and expecting different results.
--Albert Einstein

There is no record of Albert Einstein having said that. Ben Franklin and Mark Twain, are also credited with coining this idea, have no record of saying it either.

There are experiments where, if you do not get a different answer every time, you are doing something wrong.

Pass a carbon/zinc D cell around a room full of metrology technicians, engineers and managers and the voltage will go higher and higher as each person handles the cell. The first time I did this, one engineer called out, "0.546 volts." I dutifully recorded his answer on the white board. After everyone had measured the cell we talked about outliers before getting to the subject of the meeting, Statistical Analysis in Metrology.

Pass an alkaline D cell around a room full of metrology technicians, engineers and managers and the voltage will go lower and lower as each person handles the cell.

Do the measurement in a stable environment without touching anything and every time you make the measurement, you will get a different answer, sometimes higher than the last measurement and sometimes lower but never the same.

[Rufus T. Firefly]

[rogruth]

Wayne,
Is there any explanation of what you describe above with the battery measurements?

[webenda]

Wayne,
Is there any explanation of what you describe above with the battery measurements?

Yes.

[rogruth]

Wayne,
Is there any explanation of what you describe above with the battery measurements?

Yes.

OK. You did to me what I have done to others many times.

What is the explanation of the differences with the batteries?

[Rufus T. Firefly]

The definition of insanity is doing the same thing over and over and expecting different results.
--Albert Einstein

There is no record of Albert Einstein having said that. Ben Franklin and Mark Twain, are also credited with coining this idea, have no record of saying it either.

Interesting. I'd not heard that attributed to any of the 3. Sounds more like something from Will Roger though...

[E7]

The definition of insanity is doing the same thing over and over and expecting different results.
--Albert Einstein

There is no record of Albert Einstein having said that. Ben Franklin and Mark Twain, are also credited with coining this idea, have no record of saying it either.

Interesting. I'd not heard that attributed to any of the 3. Sounds more like something from Will Roger though...

It was more likely Joe Theisman attributing it to Norman Einstein.

[rogruth]

The definition of insanity is doing the same thing over and over and expecting different results.
--Albert Einstein

There is no record of Albert Einstein having said that. Ben Franklin and Mark Twain, are also credited with coining this idea, have no record of saying it either.

Interesting. I'd not heard that attributed to any of the 3. Sounds more like something from Will Roger though...

It was more likely Joe Theisman attributing it to Norman Einstein.

E,
Since you were a POGO fan you may remember that the owl and the turtle were arguing over who said "When it rains it pours". One thought Mr. Twain
and the other thought Mr. Clemens. Pogo asked the groundhog who said it and his reply was "You heard me. I said it".

[E7]

I didn't notice the second pupil, thought it was just the "Who peed in my coffee?" mug.

[webenda]

Wayne,
Is there any explanation of what you describe above with the battery measurements?

Yes.

OK. You did to me what I have done to others many times.

What is the explanation of the differences with the batteries?

That was not intentional Roger, I just did not have time at the moment.

Are you familiar with the notation, Temperature Coefficient, when used with the voltage specification for batteries?
A temperature coefficient describes the relative change of a physical property that is associated with a given change in temperature.
--Wikipedia.

There are two temperature coefficients that affect the voltage at a battery's output terminals, the resistance temperature coefficient and the voltage temperature coefficient. Because we measured the open circuit battery voltage, the resistance temperature coefficient had no measurable affect on the voltage measured.

Let's measure the voltage temperature coefficient of a battery in my parts drawer.

[webenda]

||

Temperature change = 70 - 40 = 30 F
Voltage change = 1617 mV - 1625 mV = -8 mV.
Temperature coefficient = -8 mV / 30 F or - 0.267 mV per °F.
Equation check. 1625 mV + (30 °F x -0.267 mV / °F) = 1625 mV - 8 mV = 1617 mV.

If you do this with a carbon-zinc battery you should get a positive temperature coefficient.


Edit 1: Corrected cold temperature from -22 °F to 40 °F.

[E7]

Since you were a POGO fan you may remember that the owl and the turtle were arguing over who said "When it rains it pours". One thought Mr. Twain
and the other thought Mr. Clemens. Pogo asked the groundhog who said it and his reply was "You heard me. I said it".

There's a better than even chance that ALL 3 said it, though the groundhog was somewhat after the fact. I'm thinking the other 2 were in a dead heat.

[webenda]

The temperature (voltage or resistance) of a battery is not linear over the entire operating range of the battery. If anyone wishes to find the knees in the voltage/temperature coefficient, make the measurements every degree Fahrenheit and let us know what you find.

[rogruth]

Wayne,
No problem with the "Yes" answer. I use it too often.

[Rufus T. Firefly]